Interpretive Summary: St Augustinegrass is a popular turf species grown in Florida. We are breeding St. Augustinegrass by collecting germplasm, creating somaclonal variation, and inducing mutations in attempt to improve its cold tolerance and leaf texture. Freezing tolerant germplasm is being selected by freezing clones under controlled conditions. A more cold-hardy plant will allow this important turf species to be grown as far north as North Carolina.

Technical Abstract:
St. Augustinegrass has good shade and salt tolerance. However, the lack of cold tolerance limits its application and production in North Carolina. The goal of this project is to develop new cultivars for improved cold tolerance and/or finer leaf texture. We are using approaches, such as germplasm collection and evaluation, tissue culture, and mutagenesis to achieve the goal. A total of 31 germplasm samples were collected from VA, NC, SC and TX. By testing various explant tissues and culture media, we have improved tissue culture responses of St. Augustinegrass and established an efficient culture system. Over a thousand plants have been regenerated from tissue culture so far. A couple of somaclonal variations have been observed. In addition, a cold hardening screening system in the controlled environment has been tested. Meanwhile, three field test locations with various climate conditions are established. Massive screening of the germplasm collections, the tissue culture plants and the mutated plants will be conducted in both controlled environment and in the fields.